4 ms·

> It isn't a swiss cheese failure if it was hit by an out-of-design-spec event First of all, the design basis accident is a design choice by the developers of

by cpgxiii 7mo ago

> It isn't a swiss cheese failure if it was hit by an out-of-design-spec event First of all, the design basis accident is a design choice by the developers of the plant and regulators. The decision process that produced that DBA was clearly faulty - the economic and social costs of the disaster so clearly have exceeded those of a building to a more serious DBA. > Again I'm going from memory with the numbers but doubling the cost of a rare disaster in a way that injures ... pretty much nobody ... is a great trade for cheap secure energy. It isn't a clear case that anything needs to change or even went wrong in the design process. Massive earthquakes and tsunamis aren't easy to deal with. This is absolute nonsense. For the cost of maybe maybe tens of millions at most in additional concrete to build the seawall a few meters higher, the entire disaster would have been avoided entirely (i.e. plant restored to operation). With backup cooling that could have survived the tsunami (a lower expense than building a higher seawall), all that would have happened at Fukushima Daiichi is what happened at its neighbor Fukushima Daini (plant rendered inoperable, no meltdown, no significant radioactive release). Instead, we are talking about a disaster that will cost a (current) estimated $180 billion USD to clean up (and there is no way this estimate is realistic, when the methods required to perform the cleanup barely exist yet).

roenxi 7mo ago
> The decision process that produced that DBA was clearly faulty - the economic and social costs of the disaster so clearly have exceeded those of a building to a more serious DBA. That isn't clear at all. We're effectively sampling from the entire globe and we've had 2-3x bad nuclear disasters since the 70s. Our safety standards appear to be overcautious given the relatively small amount of damage done vs ... pretty much every alternative. The designs seem to be fine. I'm still waiting to see the justification for the evacuations from Fukushima; they seemed excessive. People died. > For the cost of maybe maybe tens of millions at most... You haven't thought for long enough before you typed that. For this particular disaster, sure. But hardening against all the possible disasters is what needs to happen when you become less risk tolerant. It is the millions of dollars to prevent against this disaster multiplied by the number of potential disasters that you have to consider. Safety is expensive. The numbers aren't small, safety of that magnitude might not even be economically feasible. To say nothing of whether it is actually sensible. And once you get into one in 500 or thousand year events, some really catastrophic stuff starts happening that just can't be reasonably defended against. San Francisco and its fault springs to mind, I forget what sort of even that is but it is probably once a millennium or more often.
- drtgh 7mo ago
  Fukushima was designed to be constructed on a hill 30-35 meters above the ocean, but someones decided would be cheaper to construct it at sea level in order to reduce costs in water pumping, others decided to approve this, and much latter, one decade before the disaster when was requested to reinforce the security measures within all the reactors at Japan, those in charge of Fukushima decided to ignore it, again, pushing for extensions year after year until it all blew up. Decades of bad decisions with a strong smell to corruption. https://warp.da.ndl.go.jp/info:ndljp/pid/3856371/naiic.go.jp/en/report/ https://warp.da.ndl.go.jp/info:ndljp/pid/3856371/naiic.go.jp... https://warp.da.ndl.go.jp/info:ndljp/pid/3856371/naiic.go.jp/wp-content/uploads/2012/08/NAIIC_Eng_Chapter1_web.pdf https://warp.da.ndl.go.jp/info:ndljp/pid/3856371/naiic.go.jp... https://web.archive.org/web/20210314022059/https://carnegieendowment.org/2012/03/06/why-fukushima-was-preventable-pub-47361 https://web.archive.org/web/20210314022059/https://carnegiee...
  - roenxi 7mo ago
    I mean, ok. So say they build the plant 35m higher up, then get hit by a tsunami that is 36 meters higher [0] than the one that caused the Fukushima disaster? If we're going to start worrying about events outside the design spec we may as well talk about that one. If they're designing to tolerate an event, we can pretty reliably imagine a much worse event that will happen sooner or later and take the plant out. That is the nature of engineering. Eventually everything fails; time is generally against a design engineer. Caveating that I'm not really sure it was even an out-of-design event, but if it was then it is case closed and the swiss cheese model is an inappropriate choice of model to understand the failure. If you hit a design with things it wasn't designed to handle then it may reasonably fail because of that. [0] https://en.wikipedia.org/wiki/Megatsunami https://en.wikipedia.org/wiki/Megatsunami homework for the interested, it is cool stuff. Japan has seen some quite large waves, 57 meters seems to be the record in recent history.
    - drtgh 7mo ago
      In Japan they have the "Tsunami Stones" [0] across the coast, memorials to remind future generations of the highest point the water reached. It was negligent to construct a nuclear plant at sea level, it was just a plant waiting to be flooded, and for such case they had ten years to design protections after being requested to reinforce measures (along with the other Japanese plants), but I can imagine the ones that should put the money was not very collaborative (I even doubt if such responsible learnt the lesson). [0] https://www.smithsonianmag.com/smart-news/century-old-warnings-against-tsunamis-dot-japans-coastline-180956448/ https://www.smithsonianmag.com/smart-news/century-old-warnin... If it was a cheese model or not I do not enter (notice that parent of parent and me are different users), their negligence breaks all the possible logic we could apply without introducing the corruption's variable behind such decades of bad decisions.

by cpgxiii 7mo ago

roenxi 7mo ago

> The decision process that produced that DBA was clearly faulty - the economic and social costs of the disaster so clearly have exceeded those of a building to a more serious DBA. That isn't clear at all. We're effectively sampling from the entire globe and we've had 2-3x bad nuclear disasters since the 70s. Our safety standards appear to be overcautious given the relatively small amount of damage done vs ... pretty much every alternative. The designs seem to be fine. I'm still waiting to see the justification for the evacuations from Fukushima; they seemed excessive. People died. > For the cost of maybe maybe tens of millions at most... You haven't thought for long enough before you typed that. For this particular disaster, sure. But hardening against all the possible disasters is what needs to happen when you become less risk tolerant. It is the millions of dollars to prevent against this disaster multiplied by the number of potential disasters that you have to consider. Safety is expensive. The numbers aren't small, safety of that magnitude might not even be economically feasible. To say nothing of whether it is actually sensible. And once you get into one in 500 or thousand year events, some really catastrophic stuff starts happening that just can't be reasonably defended against. San Francisco and its fault springs to mind, I forget what sort of even that is but it is probably once a millennium or more often.

drtgh 7mo ago
Fukushima was designed to be constructed on a hill 30-35 meters above the ocean, but someones decided would be cheaper to construct it at sea level in order to reduce costs in water pumping, others decided to approve this, and much latter, one decade before the disaster when was requested to reinforce the security measures within all the reactors at Japan, those in charge of Fukushima decided to ignore it, again, pushing for extensions year after year until it all blew up. Decades of bad decisions with a strong smell to corruption. https://warp.da.ndl.go.jp/info:ndljp/pid/3856371/naiic.go.jp/en/report/ https://warp.da.ndl.go.jp/info:ndljp/pid/3856371/naiic.go.jp... https://warp.da.ndl.go.jp/info:ndljp/pid/3856371/naiic.go.jp/wp-content/uploads/2012/08/NAIIC_Eng_Chapter1_web.pdf https://warp.da.ndl.go.jp/info:ndljp/pid/3856371/naiic.go.jp... https://web.archive.org/web/20210314022059/https://carnegieendowment.org/2012/03/06/why-fukushima-was-preventable-pub-47361 https://web.archive.org/web/20210314022059/https://carnegiee...
- roenxi 7mo ago
  I mean, ok. So say they build the plant 35m higher up, then get hit by a tsunami that is 36 meters higher [0] than the one that caused the Fukushima disaster? If we're going to start worrying about events outside the design spec we may as well talk about that one. If they're designing to tolerate an event, we can pretty reliably imagine a much worse event that will happen sooner or later and take the plant out. That is the nature of engineering. Eventually everything fails; time is generally against a design engineer. Caveating that I'm not really sure it was even an out-of-design event, but if it was then it is case closed and the swiss cheese model is an inappropriate choice of model to understand the failure. If you hit a design with things it wasn't designed to handle then it may reasonably fail because of that. [0] https://en.wikipedia.org/wiki/Megatsunami https://en.wikipedia.org/wiki/Megatsunami homework for the interested, it is cool stuff. Japan has seen some quite large waves, 57 meters seems to be the record in recent history.
  - drtgh 7mo ago
    In Japan they have the "Tsunami Stones" [0] across the coast, memorials to remind future generations of the highest point the water reached. It was negligent to construct a nuclear plant at sea level, it was just a plant waiting to be flooded, and for such case they had ten years to design protections after being requested to reinforce measures (along with the other Japanese plants), but I can imagine the ones that should put the money was not very collaborative (I even doubt if such responsible learnt the lesson). [0] https://www.smithsonianmag.com/smart-news/century-old-warnings-against-tsunamis-dot-japans-coastline-180956448/ https://www.smithsonianmag.com/smart-news/century-old-warnin... If it was a cheese model or not I do not enter (notice that parent of parent and me are different users), their negligence breaks all the possible logic we could apply without introducing the corruption's variable behind such decades of bad decisions.